Current conversion device for a single- or multi-axis arrangement and operating method

A current conversion device for a single- or multi-axis arrangement, the current conversion device comprising:

• a voltage-source DC link,
• a plurality of inverters, each inverter having a DC input side connected to the voltage-source DC link and an AC output side connectable to an electric motor in one-to-one correspondence, and
• a control device operative connected to the plurality of inverters and configured to short-circuit each of the inverters,
• a measurement device configured to measure an electrical variable at each of the inverters,
• wherein the control device determines based on the measured electrical variables independently for each of the inverters directly or indirectly whether a particular inverter is feeding energy into the voltage-source DC link, and short-circuits, when this is the case, the particular inverter independently of the other inverters of the plurality of inverters,
• wherein the measured electrical variable at each of the inverters is an AC voltage measured at the AC output side, and wherein the control device short-circuits the particular inverter when one of its phase-to-phase voltages exceeds a cut-off threshold, and
• wherein each inverter comprises a plurality of identical inverter diodes and the cut-off threshold corresponds to the sum of the actual DC link voltage and twice the forward voltage of each inverter diode.